Calipers



(ModeL) W. P. DODSON.

OALIPERS.

No. 302,685. Patented July 29, 1884.

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PATENT wILsoN P. noDsoN, or PHILADELPHIA, AssiGNoR TO HIMSELF, ANDALEXANDER H. nee, or MECHANIOSBURG, PENNSYLVANIA.

CALEPERS.

ESPECIFICATION forming part of Letters Patent No. 302,685, dated July29, 1884:. Application filed February 20, 1884. (ModeLl T0 aZZ whom, itmay concern.-

Be it 'known that I, WILSON P. DODSON, a citizen of the United States,and a resident of the city and county of Philadelphia, State ofPennsylvania, have invented certain new and useful ImprovementsinCalipers, of which the following is a specification.

The object of my invention is to provide an improvement in calipers bymeans of an inexpensive applianee, the structure of which is so simpleand at the same time so readily adjustable to the recording ofmeasurements that the results attained are both rapid and reliable-anend that is indispensible in those cases in which the calipers have tobe changed from their enforced position before the measurements can berecorded.

To more fully explain my invention, reference is had to the accompanyingdrawings and letters marked thereon,which form apart of myspecification, in which similar letters refer to like parts in each ofthe figures.

Figure 1 shows a plan view of my outside calipers complete; Fig. 2 showsthe form of one of the arms detached. Fig. 3 is a modi fication ofanother possible shape. Fig. 4 shows the hub with one of the disksremoved. Fig. 5 shows a plan View of the inside calipers. Fig. 6 shows amodification of the calipers when used both for outside and insidemeasurements by the use of the same instrument.

A A are the legs, more or less curved, or of such other form as may bemost desirable or convenient, and revolving upon a pivot, D, asordinarily. The legs AA are furnished at their pivotal extremities withslotted or re-entrant shoulders to bear upon a lug, a,

whose functions in turn limit the lateral range of the legs. WVhen thecalipers are used to take a measurement, the one leg is rotated on itspivot 0 until one of the shoulders of the leg abuts against the lug a,when said leg is clamped fast thereto by the screw B. The other leg isthen rotated toward the former until the space included between the twofree ends of the legs corresponds with the measurement required, whensaid latter leg is also clamped fast thereto. The former orlug-enposition, and the legs are separated to the degree required todisengage the calipers from the object measured, when the unclamped legis again brought back to contact with its lug, and clamped fast againthereto. The position in which thelegs AA are now clamped records therequired distance or measurement. The same instrument may be used as aninside caliper, the parts being arranged substantially as shown indotted lines, Fig. 1.

In Fig. 6 I have shown a modification in which the same instrument maybe used both for outside and inside measurements simultaneously, withouttaking separate measurements respectively.

Having thus described my invention, WhatI claim, and desire to secure byLetters Patent, 1s-

1. In calipers, a hub provided with one or more stops or lugs, twopivoted arms with shoulders adapted to be brought against said lug 0rlugs, and eccentrically located clamps, whereby either or both arms maybe fixed after adjustment.

2. The combination, with the hub and arms of calipers, of one or morestops which may be brought against shoulders of one or the other of thearms after it is set, and means for clamping said stop in position toserve as a guide for resetting the arm, substantially as set forth.

3. 111 calipers, a disk' provided with a stud, an arm pivoted to thedisk and having a cutaway portion, the sides of which are adapted tobear against the stud, and another arm having a cutaway portion, andmeans for securing it in position, as set forth.

4. In calipers, the combination, with a pivoted arm and means forclamping it in position, of another arm adapted to be adjusted to adesiredv position and there secured, the first arm being also adapted tobe unclamped and moved from its first clamped position to allow theremoval of the calipers from the thing calipered, and to be restored toits said first clamped position again, thereby indicating themeasurement of the thing calipered.

5. In calipers, the combination, with a gaging arm is then releasedfromits clamped 5o pivoted arm, of means for clamping said arm, In testimonywhereof I have signed my and another arm capable of being adjusted forname to this specification in the presence of measuring distances, soconstructed that the two subscribing witnesses.

first arm may be moved from its first position, WILSON P. DODSON.

5 allowing the removal of the calipers, and re- Witnesses:

turned to its said first position after the cali- OSCAR R. MEYERs, persare so removed. OHAs. N. DUNHAM.

